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M-D Building Products - Versatile Gray Foam Backer Rod - Set 5/8in x 20ft - Essential Caulk Saver for Sealing Concrete Gaps, Expansion Joints, and Crack Filling (71506)

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$4.93

$ 1 .99 $1.99

In Stock
  • Quality Construction: This gap filler is made from high-quality, weather-resistant materials, ensuring long-lasting durability and performance. It effectively seals medium gaps between surfaces, preventing drafts and dust from entering your home. Suitable for both indoor and outdoor use, it withstands various weather conditions, providing consistent protection and improved comfort.
  • Concrete Gap Filling Excellence: Our product excels in filling concrete gaps, creating a strong foundation for caulking projects. Utilize this foam to effectively fill joints between surfaces, ensuring dependable adhesion for caulking applications that promise enduring durability and resilience.
  • Complete Gap Solution: This product provides versatile gap filling, preventing drafts and offering a sturdy base for caulking. Perfect for expansion joints in driveways and sidewalks, it can be twisted for larger gaps and easily trimmed with scissors to the desired size.
  • Effortless Installation: Enjoy a hassle-free setup by effortlessly pushing the backer rod into most joint openings until it fits snugly. Once installed, enhance the seal further by applying caulk on top—no need for messy sealants or adhesives.
  • Versatile Application: From repairing leaky roofs and window sills to addressing drafty doors, the Backer Rod is your go-to solution! Beyond sealing surface gaps, it excels in insulating, enhancing airtightness, and damp-proofing your home—offering multifaceted benefits for various household needs.



Product Description

Backer Rod Module 1
Backer Rod Module 2
excellent insulation module 3
covers most gap sizes module 4
multiple uses module 5

Manuel
2025-08-28 14:39:17
I ended up ordering the wrong size for my project and had to return. However, the backer rod seems to be made of high-quality foam, and it feels dense and durable. It has a nice, consistent texture that should be great for filling gaps and joints. I can't speak to how well it works in the long term, but it appears sturdy and like it would do the job as intended.While I didn't end up using the backer rod, Amazon's return service made the process incredibly easy and the refund was instant.
Chad
2025-08-14 19:15:30
Worked well!
Michael Parrish
2025-07-16 10:24:09
Consistent product at a good price
Charles Abney
2025-07-13 09:50:23
Very effective for covering gaps. Covers up easily.
Jimm
2025-07-12 13:38:27
Really Nice. Extremely well made. Great product. Great Shipping. Great price.
Amara
2025-05-29 11:45:46
I actually had to buy this in order to post by Doberman puppies cropped ears. This stuff is very easy to use and works wonderfully for this process. It’s easy to cut with just any kitchen scissors and obviously customize it for your needs. It has been very helpful in the process of keeping my puppies ears up straight. And I didn’t have to go to a bunch a stores to find it and have plenty of extra for any other projects I might do.
LI C.
2025-05-22 12:14:50
Great quality product.
Jeff Gardner
2025-05-16 18:43:42
Worked out just fine
Nigel Needham
2025-04-16 09:28:18
Recommended for purpose and was perfect
Sandra
2025-03-30 12:25:49
Not every store carries it so it was very convenient to have it delivered to my home next day from Amazon. Price was competitive and exactly what I needed
Greig Parry
2025-03-21 12:15:27
Excellent Product ... Works as Intended
Sarje
2025-03-20 18:12:20
This backer rod was a huge help with my caulking needs. I had some very big gaps that I would not have been able to caulk if not for the backer rod. I just wish it wasn’t so pricey as I've had to buy 3 packs (different sizes) so I’ve spent over $40 on foam. Probably cheaper than using straight caulking though, which wouldn’t have even been possible given the size of the gaps. Glad it was available when I needed it.It works best if the backer rod foam is slightly bigger than the gap, so you can squeeze the foam rod in the gap and then caulk over top of that.
Brett Kelly
2025-02-10 10:31:36
Good quality, arrived quickly.